WASHINGTON — Sen. Bill Cassidy sharply criticized Health Secretary Robert F. Kennedy Jr. and the Make America Healthy Again movement this week, arguing that confusion about vaccine safety has contributed to a resurgence of measles across the United States. “If the way that you, quote unquote, ‘are serving the American people,’ is by confusing them as to the safety and benefits of vaccines, so much so that we have people dying from vaccine-preventable diseases like they haven’t died for decades,” Cassidy said in an interview. “That’s not serving the American people — that’s doing wrong to the American people.” Cassidy, a gastroenterologist who chairs the Senate Health Committee, also described MAHA candidates and supporters as “bankrupt” and “ideologically driven.” His remarks came as Kennedy’s department moves to overhaul federal childhood vaccine policy while measles outbreaks spread nationwide. Nearly 3,300 measles cases have been confirmed in the United States this year, surpassing the roughly 2,300 cases reported in 2025. The Centers for Disease Control and Prevention has identified declining vaccination rates as a factor in recent outbreaks. In 2024, the country recorded 285 cases. Pennsylvania officials have reported four measles deaths this year, including two unvaccinated adults and two infants. CDC data, however, did not list a measles death as the underlying cause on its national records for this year at the time of the interview. Three people died from measles in 2025, according to the agency. Kennedy has repeatedly questioned established vaccine science and has promoted debunked claims about vaccine safety, despite recently saying that the measles, mumps and rubella vaccine is the most effective way to prevent infection. An official with the Department of Health and Human Services called claims that the administration is discouraging measles vaccination “absolutely fake news” and said Kennedy has consistently endorsed MMR vaccination. Cassidy cast the deciding vote to confirm Kennedy as health secretary. Asked whether he regretted that vote, Cassidy declined to answer directly. “You can’t wallow. You gotta move on,” he said. He also rejected calls for Congress to impeach Kennedy, saying such an effort “doesn’t have a snowball’s chance.” Cassidy lost a Republican primary in May but remains a key voice on health policy because of his medical background and leadership of the Senate panel overseeing Kennedy’s department. He urged parents to consult their children’s pediatricians, warning that measles can be fatal for unvaccinated children and emphasizing that the MMR vaccine is safe, effective and not associated with autism. The senator likewise declined to comment on Heidi Overton, President Donald Trump’s nominee to lead the Food and Drug Administration, until after a Senate Health Committee hearing scheduled for next week. Cassidy criticized Overton last month over her support for Trump’s and Kennedy’s vaccine agenda. The dispute comes as public-health officials and lawmakers confront outbreaks of a highly contagious disease that had become rare in the United States through widespread vaccination. Lower immunization rates leave communities more vulnerable, particularly infants too young to be fully vaccinated and people who cannot receive vaccines for medical reasons.